Xpert MTB/RIF is an automated nucleic acid amplification test (NAT) that can detect the presence of Mycobacterium tuberculosis complex (MTC) in clinical specimens as well as rifampicin (RIF) resistance resulting from rpoB mutation. Despite its high sensitivity and specificity for diagnosing tuberculosis (TB) with or without RIF resistance, the clinical performance of the test is variable. In this study, we evaluated the performance of Xpert MTB/RIF in a setting of moderate TB burden and high medical resources...

INTRODUCTION: Polymerase chain reaction (PCR) assays have shown to be useful and quick for the diagnosis of enterovirus in aseptic meningitis. The aim of our study was to analyse the changes in clinical practice after the introduction of a real-time polymerase chain reaction (RT-PCR) technique using the Xpert EV (Cepheid(®)) assay for the qualitative detection of enterovirus RNA in cerebrospinal fluid specimens from children with suspected viral meningitis. METHODS: A retrospective study was performed in children older than 1year, diagnosed with enterovirus meningitis in a third level hospital from November 2006 to February 2013...

BACKGROUND: Currently, only 62% of incident tuberculosis (TB) cases are reported to the national programme in Pakistan. Several innovative interventions are being recommended to detect the remaining 'missed' TB cases. One such intervention involved expanding contact investigation to the community using the Xpert MTB/RIF test. METHODS: This was a before and after intervention study involving retrospective record review. Passive case finding and household contact investigation was routinely done in the pre-intervention period July 2011-June 2013...

Chlamydia trachomatis/Neisseria gonorrhoeae assay performance in males is typically determined using post-swab urine, though pre-swab urine is used in practice. We collected swabs and urine from men and used the Cepheid Xpert® CT/NG sample adequacy control to determine the effect of swab collection on urine cellular content. No difference was observed.

INTRODUCTION: Mycobacterium tuberculosis Beijing genotype is gaining importance all over the world because this genotype is highly prevalent in several areas and is also frequently associated with drug resistance. AIM: To identify and determine the frequency of Beijing genotype and mix infection with Beijing and non-Beijing in west of Iran and analyse the association between Beijing genotype and drug resistance. MATERIALS AND METHODS: This cross-sectional study was conducted on 146 Tuberculosis (TB) samples collected at the TB reference laboratory in Kermanshah west of Iran from January 2014 to February 2015, Mycobacterium tuberculosis isolates from sputum samples, detected by microcopy, biochemical tests and solid culture were included and then the confirmed samples with Cepheid Xpert MTB/RIF assay were subjected to drug susceptibility tests for rifampicin, isoniazid, ethambutol using proportional method...

To assess the performance of Xpert MTB/RIF, an automated molecular test for Mycobacterium tuberculosis (MTB) and resistance to rifampin (RIF), against smear microscopy and culture method for diagnosis of MTB infection. Methods: This is a retrospective analysis of 103 respiratory and 137 non-respiratory patient specimens suspected of tuberculosis at King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia performed between April 2014 and March 2015. Each sample underwent smear microscopy, mycobacterial culture, and GeneXpert MTB/RIF test...

Tuberculosis (TB) is a major cause of worldwide mortality. We report the case of a non-HIV-infected woman with clinical suspicion of pleural tuberculosis and contradictory results between Xpert(®) MTB/RIF and Abbott RealTime MTB assays from pleural fluid specimen. Liquid and solid cultures for tuberculosis were performed with negative results. The patient received treatment, and clinical improvement was observed. Both techniques detect Mycobacterium tuberculosis complex, but they have different targets and limits of detection...

Propidium monoazide (PMA) penetrates non-viable cells with compromised membranes. PMA has been proposed to improve the specificity of Xpert MTB/RIF (Xpert) for the detection of viable Mycobacterium tuberculosis. This study assessed the effect of PMA on Xpert cycle thresholds (CT) of M. tuberculosis made non-viable under antibiotic pressure. In vitro, we measured the difference between CT with and without PMA (ΔCT) in liquid cultures treated with one of six anti-tuberculosis drugs (isoniazid, rifampin, pyrazinamide, ethambutol, streptomycin, moxifloxacin) and found significant ΔCT only with isoniazid and ethambutol for pan-susceptible M...

Nucleic acid amplification tests for Mycobacterium tuberculosis (MTB) detection from sputum are highly sensitive and specific with smear microscopy positive specimens, but their sensitivity with smear-negative/culture-positive specimens is much lower; therefore, these tests cannot rule out a tuberculosis diagnosis. Co-extraction of PCR inhibitors may be a cause of decreased test sensitivity. Here the design and early validation of a MTB screening assay with sample preparation and qPCR methods designed to specifically address this diagnostic gap is reported...

The 2015 represent the deadline for the global tuberculosis (TB) targets set through the Millennium Development Goals (MDG). From 2016 and onward, new goals were set to end the global TB epidemic via implementing new campaign entitled "the End TB Strategy". The major hurdle to end TB epidemic in several parts of the world is the emergence and spread of drug resistant Mycobacterium tuberculosis (MTB) strains. The better understanding of the actual global burden of drug resistant tuberculosis would feed into better implementing the End TB Strategy...

OBJECTIVE: The study objectives were to determine the incidence of aminoglycoside-induced ototoxicity in institutionalized patients on intensive phase of therapy for drug-resistant Tuberculosis (DR Tb) and also to assess clinical factors which could predict the ototoxicity. METHODS: The study was a prospective analytical study among consecutive DR Tb patients who were admitted for intensive phase of therapy (of 4 months) at the DR-Tb center over a 12-month period...

Clostridium difficile is a major cause of nosocomial antibiotic-associated infectious diarrhea and pseudomembranous colitis. Detection of C. difficile by anaerobic bacterial culture and/or cytotoxicity assays has been largely replaced by rapid enzyme immunoassays (EIA). However, due to the lack of sensitivity of stool EIA, we developed a multiplex real-time PCR assay targeting the C. difficile toxin genes tcdB. stool samples from hospitalized pediatric patients suspected of having C. difficile-associated disease were prospectively collected...

BACKGROUND: Early mortality among HIV-positive adults starting antiretroviral therapy (ART) remains high in resource-limited settings, with tuberculosis (TB) the leading cause of death. However, current methods to estimate TB-related deaths are inadequate and most autopsy studies do not adequately represent those attending primary health clinics (PHCs). This study aimed to determine the autopsy prevalence of TB and other infections in adults enrolled at South African PHCs in the context of a pragmatic trial of empiric TB treatment ("TB Fast Track")...

BACKGROUND: Tuberculosis control program of Rwanda is currently phasing in light emitting diode-fluorescent microscopy (LED-FM) as an alternative to Ziehl-Neelsen (ZN) smear microscopy. This, alongside the newly introduced Xpert (Cepheid, Sunnyvale, CA, USA) is expected to improve diagnosis of tuberculosis and detection of rifampicin resistance in patients at health facilities. We assessed the accuracy of smear microscopy and the incremental sensitivity of Xpert at tuberculosis laboratories in Rwanda...

OBJECTIVE: We describe baseline characteristics, time to treatment initiation and interim patient outcomes at a decentralized, outpatient treatment site for rifampicin-resistant TB (RR-TB). METHODS: Prospective observational cohort study of RR-TB patients from March 2013 until December 2014. Study subjects were followed until completion of the intensive phase of treatment (6 months), transfer out, or a final outcome (loss from treatment (LFT) or death). RESULTS: 214 patients with RR-TB were enrolled in the study...

BACKGROUND: Adults being investigated for TB in South Africa experience high mortality, yet causes of death (CoD) are not well defined. We determined CoD in this population using verbal autopsy (VA), and compared HIV- and TB-associated CoD using physician-certified verbal autopsy (PCVA) and InterVA-4 software. METHODS: All contactable consenting caregivers of participants who died during a trial comparing Xpert MTB/RIF to smear microscopy were interviewed using the WHO VA tool...

BACKGROUND: Lower respiratory tract infection in children is increasingly thought to be polymicrobial in origin. Children with symptoms suggestive of pulmonary tuberculosis (PTB) may have tuberculosis, other respiratory tract infections or co-infection with Mycobacterium tuberculosis and other pathogens. We aimed to identify the presence of potential respiratory pathogens in nasopharyngeal (NP) samples from children with suspected PTB. METHOD: NP samples collected from consecutive children presenting with suspected PTB at Red Cross Children's Hospital (Cape Town, South Africa) were tested by multiplex real-time RT-PCR...

STUDY OBJECTIVE: We seek to use a novel layered-surveillance approach to localize influenza clusters within an acute care population. The first layer of this system is a syndromic surveillance screen to guide rapid polymerase chain reaction testing. The second layer is geolocalization and cluster analysis of these patients. We posit that any identified clusters could represent at-risk populations who could serve as high-yield targets for preventive medical interventions. METHODS: This was a prospective observational surveillance study...